Today’s installment of campaign-related news items that won’t necessarily generate a post of their own, but may be of interest to political observers:

* Sen. Jim DeMint (R) will host a Labor Day event in South Carolina for all the leading Republican presidential candidates, but in a bit of a surprise, Mitt Romney has decided not to attend. Rick Perry, Michele Bachmann, Ron Paul, Herman Cain and Newt Gingrich have accepted DeMint’s invitation.

* Rick Perry has signed the controversial Susan B. Anthony anti-abortion pledge, which makes a variety of right-wing commitments, including vowing to nominate like-minded judges and pushing to defund Planned Parenthood.

* Eric Fehrnstrom, a leading adviser to Sen. Scott Brown (R-Mass.), accidentally outed himself as the Republican activist behind a Twitter account mocking Democratic Senate candidate Alan Khazei. Fehrnstrom has refused to apologize, and the incident undermines Brown’s claim about running an above-board campaign.

* The Perry campaign is poised to pick up its first Senate endorsement, with Sen. James Inhofe (R-Okla.) throwing his support to the Texas governor.

* Erick Erickson would be more willing to look at George Allen’s (R) Senate primary opponents in Virginia, were it not for the fact that the company that publishes is aligned with Allen.

* The Republican presidential nominating calendar is far from resolved, with Arizona Gov. Jan Brewer (R) still threatening to hold a primary on Jan. 31, two weeks before Iowa’s scheduled caucus date.

* And speaking of Arizona, Democrats do not yet have a top-tier Senate candidate to run next year, but Richard Carmona, the former Surgeon General and Vietnam vet, is reportedly in the mix.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.